No abstract

therapy (RT), then 3 months (mo) and 12 mo post RT. Pts were evaluated as intent-to-treat with repeated measures mixed models were utilized to determine changes in QOL and MBSImP over time. Results: There were 61 evaluable pts with a median follow up of 22 mo (range, 4.3 e 42.7 mo). Majority were males (92.1%) with p16 positive OPC (98.4%). Forty-eight (76.2%) received adjuvant PBT. All pts are alive at the time of analysis. There was one local recurrence and one regional recurrence out of 53 pts with a minimum follow-up of 12 mo. Six pts (5, dermatitis and 1, nausea) reported grade 3 adverse events during treatment with no grade 3 or higher adverse events reported at 3 mo post PBT and beyond. Two pts on the IMRT arm required short-term PEG tube placement during treatment secondary to significant nausea due to dysgeusia. Pts noted significant QOL benefits over time in the pain, swallowing, senses, speech, contact, and mouth opening domains (all p < 0.04) except for dry mouth (p<0.0001). PBT pts particularly noted improvement in swallowing (p Z 0.1), eating (p Z 0.1), feeding tube use (p Z 0.04), and weight loss (p Z 0.07) QOL domains over time compared to IMRT. MBSImP overall severity score as well as oral and pharyngeal impairment scores showed no significant change over time, with average overall severity score of 6.72 (95% CI: 6.61, 6.83), oral impairment score of 1.27 (95% CI: 1.01, 1.53) and an average pharyngeal impairment score of 3.44 (95% CI: 2.92, 3.96). Performance Status Scale for normalcy of diet (p Z 0.01) and speech (p < 0.1) improved significantly over time. Conclusion: Mucosal sparing PBT is tolerated well in resected OPC with a reduced toxicity burden evidenced by no change or improvement compared to baseline in toxicity rates, QOL scores, and MBSImP over time. Local recurrence rates at 12 months are low.